In Jim Forest’s biography of Dorothy Day, he mentions that Upton Sinclair’s muckraking novel The Jungle “inspired Day to take long walks in poor neighborhoods in Chicago’s South Side,” a precursor to her involvement in politics.

The Jungle, written in 1906 (the same year the Day family moved into an apartment in Chicago’s South Side), focuses on the harsh realities of poverty, abhorrent working and living conditions, and depicts corruption (focusing directly on the American meatpacking industry). For instance, he spends a few chapters talking about the “lie of the American dream.” It is unsurprising, given the book’s content, that Day was struck by it. Although fictional, Sinclair’s book painted very realistic circumstances, and the author himself had spent seven weeks undercover in 1904, working in different plants within Chicago.

After looking around online, I found a pertinent quote from The Jungle that details the essence of its depiction of poverty:
“Here was a population, low-class and mostly foreign, hanging always on the verge of starvation, and dependent for its opportunities of life upon the whim of men every bit as brutal and unscrupulous as the old-time slave drivers; under such circumstances immorality was exactly as inevitable, and as prevalent, as it was under the system of chattel slavery. Things that were quite unspeakable went on there in the packing houses all the time, and were taken for granted by everybody; only they did not show, as in the old slavery times, because there was no difference in color between master and slave."